- •Preface
- •Introduction
- •Lesson Objectives
- •Lesson Agenda
- •Course Objectives
- •Course Agenda
- •Appendixes Used in the Course
- •Lesson Agenda
- •Oracle Database 11g: Focus Areas
- •Oracle Database 11g
- •Oracle Fusion Middleware
- •Oracle Enterprise Manager Grid Control 10g
- •Oracle BI Publisher
- •Lesson Agenda
- •Relational and Object Relational Database Management Systems
- •Data Storage on Different Media
- •Relational Database Concept
- •Definition of a Relational Database
- •Data Models
- •Entity Relationship Model
- •Relating Multiple Tables
- •Relational Database Terminology
- •Lesson Agenda
- •Using SQL to Query Your Database
- •SQL Statements
- •Development Environments for SQL
- •Lesson Agenda
- •The Human Resources (HR) Schema
- •Tables Used in the Course
- •Lesson Agenda
- •Oracle Database 11g Documentation
- •Additional Resources
- •Summary
- •Practice I: Overview
- •Objectives
- •Lesson Agenda
- •Capabilities of SQL SELECT Statements
- •Basic SELECT Statement
- •Selecting All Columns
- •Selecting Specific Columns
- •Writing SQL Statements
- •Column Heading Defaults
- •Lesson Agenda
- •Arithmetic Expressions
- •Using Arithmetic Operators
- •Operator Precedence
- •Defining a Null Value
- •Null Values in Arithmetic Expressions
- •Lesson Agenda
- •Defining a Column Alias
- •Using Column Aliases
- •Lesson Agenda
- •Concatenation Operator
- •Literal Character Strings
- •Using Literal Character Strings
- •Alternative Quote (q) Operator
- •Duplicate Rows
- •Lesson Agenda
- •Displaying the Table Structure
- •Using the DESCRIBE Command
- •Quiz
- •Summary
- •Practice 1: Overview
- •Objectives
- •Lesson Agenda
- •Limiting Rows Using a Selection
- •Limiting the Rows That Are Selected
- •Using the WHERE Clause
- •Character Strings and Dates
- •Comparison Operators
- •Using Comparison Operators
- •Range Conditions Using the BETWEEN Operator
- •Membership Condition Using the IN Operator
- •Pattern Matching Using the LIKE Operator
- •Combining Wildcard Characters
- •Using the NULL Conditions
- •Defining Conditions Using the Logical Operators
- •Using the AND Operator
- •Using the OR Operator
- •Using the NOT Operator
- •Lesson Agenda
- •Rules of Precedence
- •Lesson Agenda
- •Using the ORDER BY Clause
- •Sorting
- •Lesson Agenda
- •Substitution Variables
- •Using the Single-Ampersand Substitution Variable
- •Character and Date Values with Substitution Variables
- •Specifying Column Names, Expressions, and Text
- •Using the Double-Ampersand Substitution Variable
- •Lesson Agenda
- •Using the DEFINE Command
- •Using the VERIFY Command
- •Quiz
- •Summary
- •Practice 2: Overview
- •Objectives
- •Lesson Agenda
- •SQL Functions
- •Two Types of SQL Functions
- •Single-Row Functions
- •Lesson Agenda
- •Character Functions
- •Case-Conversion Functions
- •Using Case-Conversion Functions
- •Character-Manipulation Functions
- •Using the Character-Manipulation Functions
- •Lesson Agenda
- •Number Functions
- •Using the ROUND Function
- •Using the TRUNC Function
- •Using the MOD Function
- •Lesson Agenda
- •Working with Dates
- •RR Date Format
- •Using the SYSDATE Function
- •Arithmetic with Dates
- •Using Arithmetic Operators with Dates
- •Lesson Agenda
- •Date-Manipulation Functions
- •Using Date Functions
- •Using ROUND and TRUNC Functions with Dates
- •Quiz
- •Summary
- •Practice 3: Overview
- •Objectives
- •Lesson Agenda
- •Conversion Functions
- •Implicit Data Type Conversion
- •Explicit Data Type Conversion
- •Lesson Agenda
- •Using the TO_CHAR Function with Dates
- •Elements of the Date Format Model
- •Using the TO_CHAR Function with Dates
- •Using the TO_CHAR Function with Numbers
- •Using the TO_NUMBER and TO_DATE Functions
- •Using the TO_CHAR and TO_DATE Function with RR Date Format
- •Lesson Agenda
- •Nesting Functions
- •Lesson Agenda
- •General Functions
- •NVL Function
- •Using the NVL Function
- •Using the NVL2 Function
- •Using the NULLIF Function
- •Using the COALESCE Function
- •Lesson Agenda
- •Conditional Expressions
- •CASE Expression
- •Using the CASE Expression
- •DECODE Function
- •Using the DECODE Function
- •Quiz
- •Summary
- •Practice 4: Overview
- •Objectives
- •Lesson Agenda
- •What Are Group Functions?
- •Types of Group Functions
- •Group Functions: Syntax
- •Using the AVG and SUM Functions
- •Using the MIN and MAX Functions
- •Using the COUNT Function
- •Using the DISTINCT Keyword
- •Group Functions and Null Values
- •Lesson Agenda
- •Creating Groups of Data
- •Creating Groups of Data: GROUP BY Clause Syntax
- •Using the GROUP BY Clause
- •Grouping by More than One Column
- •Using the GROUP BY Clause on Multiple Columns
- •Illegal Queries Using Group Functions
- •Restricting Group Results
- •Restricting Group Results with the HAVING Clause
- •Using the HAVING Clause
- •Lesson Agenda
- •Nesting Group Functions
- •Quiz
- •Summary
- •Practice 5: Overview
- •Objectives
- •Lesson Agenda
- •Types of Joins
- •Joining Tables Using SQL:1999 Syntax
- •Qualifying Ambiguous Column Names
- •Lesson Agenda
- •Creating Natural Joins
- •Retrieving Records with Natural Joins
- •Creating Joins with the USING Clause
- •Joining Column Names
- •Retrieving Records with the USING Clause
- •Using Table Aliases with the USING Clause
- •Creating Joins with the ON Clause
- •Retrieving Records with the ON Clause
- •Creating Three-Way Joins with the ON Clause
- •Applying Additional Conditions to a Join
- •Lesson Agenda
- •Joining a Table to Itself
- •Self-Joins Using the ON Clause
- •Lesson Agenda
- •Nonequijoins
- •Retrieving Records with Nonequijoins
- •Lesson Agenda
- •INNER Versus OUTER Joins
- •LEFT OUTER JOIN
- •RIGHT OUTER JOIN
- •FULL OUTER JOIN
- •Lesson Agenda
- •Cartesian Products
- •Generating a Cartesian Product
- •Creating Cross Joins
- •Quiz
- •Summary
- •Practice 6: Overview
- •Objectives
- •Lesson Agenda
- •Using a Subquery to Solve a Problem
- •Subquery Syntax
- •Using a Subquery
- •Guidelines for Using Subqueries
- •Types of Subqueries
- •Lesson Agenda
- •Single-Row Subqueries
- •Executing Single-Row Subqueries
- •Using Group Functions in a Subquery
- •The HAVING Clause with Subqueries
- •What Is Wrong with This Statement?
- •No Rows Returned by the Inner Query
- •Lesson Agenda
- •Multiple-Row Subqueries
- •Lesson Agenda
- •Null Values in a Subquery
- •Quiz
- •Summary
- •Practice 7: Overview
- •Objectives
- •Lesson Agenda
- •Set Operators
- •Set Operator Guidelines
- •The Oracle Server and Set Operators
- •Lesson Agenda
- •Tables Used in This Lesson
- •Lesson Agenda
- •UNION Operator
- •Using the UNION Operator
- •UNION ALL Operator
- •Using the UNION ALL Operator
- •Lesson Agenda
- •INTERSECT Operator
- •Using the INTERSECT Operator
- •Lesson Agenda
- •MINUS Operator
- •Using the MINUS Operator
- •Lesson Agenda
- •Matching the SELECT Statements
- •Matching the SELECT Statement: Example
- •Lesson Agenda
- •Using the ORDER BY Clause in Set Operations
- •Quiz
- •Summary
- •Practice 8: Overview
Using the TO_CHAR Function with Dates
TO_CHAR(date, 'format_model')
The format model:
•Must be enclosed with single quotation marks
•Is case-sensitive
•Can include any valid date format element
•Has an fm element to remove padded blanks or suppress leading zeros
•Is separated from the date value by a comma
Copyright © 2009, Oracle. All rights reserved.
Using the TO_CHAR Function with Dates |
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TO_CHAR converts a datetime data type to a valueOracleof VARCHAR2 data type in the format specified
by the format_model. A format model is a character literal that describes the format of datetime stored in a character string. For example, the datetime fo m t model for the string '11-Nov-
1999' is 'DD-Mon-YYYY'. You can use the TO CHAR function to convert a date from its default format to the one that you specify.
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value from the format model with a comma.
• The names of days and months in the output are automatically padded with blanks.
• To remove padded blanks or to suppress leading zeros, use the fill mode fm element.
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Oracle Database 11g: SQL Fundamentals I 4 - 11
Elements of the Date Format Model
Element |
Result |
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YYYY |
Full year in numbers |
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YEAR |
Year spelled out (in English) |
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MM |
Two-digit value for the month |
MONTH |
Full name of the month |
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MON |
Three-letter abbreviation of the month |
DY |
Three-letter abbreviation of the day of the week |
DAY |
Full name of the day of the week |
DD |
Numeric day of the month |
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Oracle Database 11g: SQL Fundamentals I 4 - 12
Sample Format Elements of Valid Date Formats
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SCC or CC |
Century; server prefixes B.C. date with - |
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Years in dates YYYY or SYYYY |
Year; server prefixes B.C. date with - |
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YYY or YY or Y |
Last three, two, or one digit of the year |
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Y,YYY |
Year with comma in this position |
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IYYY, IYY, IY, I |
Four-, three-, two-, or one-digit year based on the ISO |
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SYEAR or YEAR |
Year spelled out; server prefixes B.C. date with - |
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BC or AD |
Indicates B.C. or A.D. year |
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B.C. or A.D. |
Indicates B.C. or A.D. year using periods |
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Q |
Quarter of year |
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MM |
Month: two-digit value |
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Name of the month padded with blanks to a length of nine |
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MON |
Name of the month, three-letter abbreviation |
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RM |
Roman numeral month |
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Julian day; the number of days sinceAcademyDecember 31, 4713 |
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WW or W |
Week of the year or month |
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DDD or DD or D |
Day of the year, month, or week |
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DAY |
Name of the day padded with blanks to a length of nine |
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DY |
Name of the day; three-letter abbreviation |
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B.C. |
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IW |
Weeks in the year from ISO standard (1 to 53) |
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Oracle Database 11g: SQL Fundamentals I 4 - 13
Elements of the Date Format Model
•Time elements format the time portion of the date:
HH24:MI:SS AM |
15:45:32 PM |
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DD "of" MONTH |
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12 of OCTOBER |
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• Number suffixes spell out numbers: |
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ddspth |
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fourteenth |
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Elements of the Date Format Model |
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Use the formats that are listed in the following tables to display time information and literals, and to |
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change numerals to spelled numbers. |
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AM or PM |
Meridian indicator |
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A.M. or P.M. |
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Meridian indicator with periods |
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HH or HH12 or HH24 |
Hour of day, or hour (1–12), or hour (0–23) |
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MI |
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Mi ute (0–59) |
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SS |
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Second (0–59) |
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SSSSS |
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Seconds past midnight (0–86399) |
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Oracle Database 11g: SQL Fundamentals I 4 - 14
Other Formats
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Description |
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/ . , |
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Punctuation is reproduced in the result. |
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“of the” |
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Quoted string is reproduced in the result. |
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Specifying Suffixes to Influence Number Display |
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Element |
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Description |
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TH |
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Ordinal number (for example, DDTH for 4TH) |
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SP |
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Spelled-out number (for example, DDSP for FOUR) |
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SPTH or THSP |
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Spelled-out ordinal numbers (for example, DDSPTH for |
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FOURTH) |
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Oracle Database 11g: SQL Fundamentals I 4 - 15